相关实验视频
Updated: Jul 27, 2025

16:14
Trajectory Data Analyses for Pedestrian Space-time Activity Study
Published on: February 25, 2013
13.6K
重新审视图形横向编辑距离及其变体的复杂性和算法
Yutong Qiu1, Yihang Shen1, Carl Kingsford1
1Computational Biology Department, School of Computer Science, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA.
ArXiv
|June 9, 2023
概括
图形横向编辑距离 (GTED) 是NP完整的,这与之前关于多项式可解性的说法相矛盾. 为准确的基因组图比较提供了新的整数线性编程公式.
科学领域:
- 计算生物学是一种计算生物学.
- 图形理论是指图形的理论.
- 生物信息学是一种生物信息学.
背景情况:
- 图形横向编辑距离 (GTED) 提供了一种方法,通过分析de Bruijn图形来比较物种的进化关系.
- 之前的工作声称GTED是多项式可解决的,建议整数线性编程 (ILP) 配方.
研究的目的:
- 解决关于GTED的相互矛盾的复杂性结果.
- 为GTED提供正确的ILP配方,并评估其效率.
主要方法:
- 证明GTED的NP完整性.
- 开发和评估GTED的新型ILP配方.
- 分析之前的ILP方法的局限性.
主要成果:
- 已经证明GTED是NP完整的,这与之前的多项式时间可解决性要求相矛盾.
- 之前的ILP配方被证明可以计算GTED的下界,而不是确切的距离,并且不能在多项式时间中解决.
- 为GTED开发了两种新的正确ILP配方,并评估了它们的经验效率.
结论:
- 这项工作为比较基因组图建立了严格的算法基础.
- 这些发现需要对GTED应用进行重新评估,并建议开发启发式方法.
相关概念视频
Adjusting a Traverse
86
In the site survey of a four-sided traverse, internal angles are essential to ensure geometric accuracy. The survey revealed that the sum of the measured internal angles was 359 degrees and 48 minutes, which is 12 minutes less than the expected 360 degrees. This discrepancy signals an error likely arising from measurement inaccuracies during the fieldwork.To rectify this error, the adjustment process involved distributing the 12-minute shortfall equally across the four internal angles. By...
86
Manipulation and Analysis
47
GIS manipulation and analysis functions are vital for decision-making and planning. These activities range from data retrieval tasks, such as selecting information based on specific criteria, to advanced analytical techniques that address complex spatial problems.One critical GIS analysis method is overlaying, which combines multiple data layers to examine impacts. For example, overlaying a river-dammed lake boundary with road networks can identify affected infrastructure. Another common...
47
Trial and Error and Algorithm
153
A problem-solving strategy is a plan of action used to find a solution. Different strategies have distinct action plans. Trial and error involves trying different solutions until one works. For instance, to fix a broken printer, you might check ink levels, ensure the paper tray isn't jammed, and verify the printer's connection to your laptop. This method can be time-consuming but is commonly used. Thomas Edison, for example, used trial and error to find a suitable filament for the light...
153
Vector Algebra: Graphical Method
12.5K
Vectors can be multiplied by scalars, added to other vectors, or subtracted from other vectors. The vector sum of two (or more) vectors is called the resultant vector or, for short, the resultant.
We use the laws of geometry to construct resultant vectors, followed by trigonometry to find vector magnitudes and directions. For a geometric construction of the sum of two vectors in a plane, we follow the parallelogram rule. Suppose two vectors are at arbitrary positions. Translate either one of...
We use the laws of geometry to construct resultant vectors, followed by trigonometry to find vector magnitudes and directions. For a geometric construction of the sum of two vectors in a plane, we follow the parallelogram rule. Suppose two vectors are at arbitrary positions. Translate either one of...
12.5K
Design Example: Traverse Angle Computations
112
Traverse angle computations are a critical component of surveying, used to compute the internal angles within a closed traverse. A traverse consists of a series of connected lines forming a closed loop, often used for land boundary delineation or mapping. Calculating the internal angles ensures accuracy in the traverse geometry and is essential for checking survey data integrity.The process begins with known azimuths and bearings of the traverse sides. Internal angles at each vertex are...
112
Distance Corrections
53
To achieve precise distance measurements, especially in surveying and construction, certain corrections must be applied to account for potential sources of error like the standardization errors, temperature variations, and slope adjustments.Standardization error emerges when measurement equipment undergoes changes, such as wear, repairs, or weather impacts. To address this, surveyors compare the equipment’s readings to a standard. This process identifies any deviation that might lead to...
53

